The publishing of the English version of Dr. Raudive’s 1968 book Unhörbares wird hörbar (“What is inaudible becomes audible”) was contingent upon Dr. Raudive conducting a series of experiments in London for the prospective publisher.

So………on Friday, December 12, 1969, Dr. Raudive arrived in Britain and brought along his equipment including a “diode box”.

On page x of the preface to Breakthrough the diode box is described as a small box twice the size of a match-box with 2 inches of wire sticking out of one end and another small wire at the other end which was to be placed into the input of a tape recorder.

Not understanding the diode’s function or wondering if this diode box was some type of elaborate hoax, one of the publishers arranged for the diode to be inspected by David Stanley; an electrical engineer.

The following day, Mr. Stanley inspected the diode box and within seconds proclaimed the diode and circuit was ordinary and held no particular value. He offered to build another diode box within the hour for the publisher to use during their experiments later that evening.

On page xx of the preface to Breakthrough we find David Stanley’s schematic of Dr. Raudive’s diode circuit as it appeared on December 13, 1969.

Even though there are no values listed for parts, the schematic clearly shows the diode circuit had evolved from Diagram 1 (shown above) to one which included a double coil and capacitor.